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AC and DC cable wiring CoC


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Hi Guys

Looked around a bit on the forum but did not see a specific section on this (sorry if I missed it).

From a CoC perspective, I was told that AC and DC wires are not allowed to run next to one another in the same conduit (trunking).

Is this correct? If you look at the layout of the ports of most inverters you are bond to have AC and DC lines crossing one another depending on layout restrictions.

What is the correct approach here?

 

Thanks

 

 

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as far as i know, the regulations do state that ac and dc wires cannot be in the same trunking, I am sure it is because of a safety issue, so that you cannot by mistake connect an ac source to a dc source. i know of an installer will put a next size smaller trunking in larger trunking

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34 minutes ago, branderplank said:

Hi Guys

Looked around a bit on the forum but did not see a specific section on this (sorry if I missed it).

From a CoC perspective, I was told that AC and DC wires are not allowed to run next to one another in the same conduit (trunking).

Is this correct? If you look at the layout of the ports of most inverters you are bond to have AC and DC lines crossing one another depending on layout restrictions.

What is the correct approach here?

 

Thanks

 

 

Mine run in the same trunking and have CoC. I did the installation myself and had an independent Electrical company do CoC for the installation.  

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coc or no coc, if there is a fire and the assessor for some reason figures the problem is with the ac and dc wires being in the same trunking, the insurance company can reject your claim can be thrown out

    i asked my insurance company regarding coc's, they said the coc is fine , but if they find a violation of the code, they can reject the claim

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2 hours ago, Tariq said:

coc or no coc, if there is a fire and the assessor for some reason figures the problem is with the ac and dc wires being in the same trunking, the insurance company can reject your claim can be thrown out

    i asked my insurance company regarding coc's, they said the coc is fine , but if they find a violation of the code, they can reject the claim

How will they prove that I didn't have the wires in two separate, parallel trunckings when every thing has burned down to ashes? Plastic trunking will completely melt and the insulation of the wires. 

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5 minutes ago, Vassen said:

🤣 in the best case, everything would melt and collapse and there would be no evidence. 
 

however, it doesn’t always work like that. If you’ve used wall plugs to mount the trunking, you would be able to count how many holes you’ve drilled. The plastic and insulation may burn away but the copper wire will still be there and you would be able to tell that they were close together in the first place. To avoid paying out a million or 2, insurance companies would look for any loopholes or installation issues to not pay out. If the install is not according to regulations, you have no case. 
 

further, if someone is injured or there is loss of life, then it also becomes a criminal case. 

I can say the second trunking was mounted with hot glue and was running parallel to the DC wire trunking. Loss of life or injury when CoC was issued by a qualified electrician, will be the electrician's liability 🙂

 

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Some interesting discussion here

It seems the writing is on the wall

i will have to change my installation 🤔

Did not know about the metal trunking - if you look at the gallery of the power forum store it all looks like plastic trunking and in some instances ac and dc in the same conduit?

Question, does SANS 10142-1:2017 Edition 2 prescribe the minimum or is it a "good practice" guide.

Who regulates the wiring code? Is it not an NRS function? I.e. NRS 097-2-1:2010 Edition 1

(Not my pictures - just copied from the website)

7476_974_IMG_2730.png.e01b63e86e46de2694d4fd9f1c148ddb.png?v=1590950564

3958_6777_IMG_20171102_112941.thumb.jpg.4399f630ec969b8bb11ce0b41deac8d7__1_.jpg?v=1590950585

5382_3711_IMG_20171030_141444.thumb.jpg.b9355a606fce3e7e461430258483c268.jpg?v=1590950568

 

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56 minutes ago, branderplank said:

Question, does SANS 10142-1:2017 Edition 2 prescribe the minimum or is it a "good practice" guide.

SANS 10142-1:2017 Edition 2: Wiring of premises isn't a suggestion book.  It lists the rules and requirements for a domestic install.  There are no "hey do what you want but we recommend".  Pretty much each section lays out a number of rules related to a specific topic.

They even go further to say you shouldn't put AC from one power source in the same conduit as another AC power source (ie. you can't run you inverter AC wire in the same conduit as your Eskom AC).

But the DC requirement is pretty obvious unless you don't know what you are doing.  Almost everything in SANS 10142-1:2017 is about safety.  And when you run AC and DC in the same conduit, if any cable were to get nicked and get in contact with the other, your entire DC installation is at mains voltage without any of the AC safety equipment.  Nicked cables are the most common cause of electrical faults and happen in most homes, so it is an obvious rule.

56 minutes ago, branderplank said:

Who regulates the wiring code?

South African Bureau of standards.  These SANS document regulate every industry.  Plumbing, Electrical, Buildings, etc.  Just about anything that is legal to use in this country will either state which SANS codes they comply with in the manual or on the product itself.  You can't legally sell almost anything in SA without complying with one or more of the SANS standards.

7 hours ago, FixAMess said:

FYI - DC wiring is supposed to run in metal trunking, not plastic trunking.....

Where does it say that?  I just logged into my access portal to make sure I have the latest edition and I can't find anything about that in the standard.

Edited by Gnome
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I deal with this crap on a daily basis ... the problem in the electrcial industry is not the standards (they change all the time to attempt to create a safer environment for YOU) ... its the customer support ... no policing in the industry ... it seems we dont have enough suitably qualified people working in the DOL to investigate illegal installtations ... another issue ... you as the customer have to file a complaint ... then pay for the investigation ... then get quotes to get the installation bought up to standard ... pay for it to be done ... then claim all the costs from the contractor who did the illegal installation ( I wish you luck with that ... you gonna need it)

To clear up something else  ... yes YOU as the customer are responsible for the electrical installation on your property ... it is your responsibilty to employ the services of a sutiably qualified person/company to carry out work on your property ... if you want to DIY ... and break the rules or get someone to sign over the project on completion without even following the progress ... or advising you of the correct proceedures ... its all on YOU. 

I know of installations which have been signed off without the inspector even visitng the site ... then people cry when the insurnace company rejects claims ... It is not pleasant when you get called out to an investigation where a 2 year old child is dead because some clever dick decided ... disconnecting his stove DIY ... leaving the wires exposed ... was a cheaper option.

I went to a fire where fortunately the aircon exploded and blew out across the room and hit the kitchen cupboard ... waking up the eperson who was asleep in the  granny flat... it pretty much saved her life ... the building was guttered ... until it happens to you or you see the result of your actions ... rules and regs are not that important ;)

Now with every man and his dog being experts in this field ... it just makes it that much worse. 

 

 

 

 

 

 

 

 

Edited by isetech
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8 minutes ago, isetech said:

I deal with this crap on a daily basis ... the problem in the electrcial industry is not the standards (they change all the time to attempt to create a safer environment for YOU) ... its the customer support ... no policing in the industry ... it seems we dont have enough suitably qualified people working in the DOL to investigate illegal installtations ... another issue ... you as the customer have to file a complaint ... then pay for the investigation ... then get quotes to get the installation bought up to standard ... pay for it to be done ... then claim all the costs from the contractor who did the illegal installation ( I wish you luck with that ... you gonna need it)

To clear up something else  ... yes YOU as the customer are responsible for the electrical installation on your property ... it is your responsibilty to employ the services of a sutiably qualified person/company to carry out work on your property ... if you want to DIY ... and break the rules or get someone to sign over the project on completion without even following the progress ... or advising you of the correct proceedures ... its all on YOU. 

I know of installations which have been signed off without the inspector even visitng the site ... then people cry when the insurnace company rejects claims ... It is not pleasant when you get called out to an investigation where a 2 year old child is dead because some clever dick decided ... disconnecting his stove DIY ... leaving the wires exposed ... was a cheaper option.

I went to a fire where fortunately the aircon exploded and blew out across the room and hit the kitchen cupboard ... waking up the eperson who was asleep in the  granny flat... it pretty much saved her life ... the building was guttered ... until it happens to you or you see the result of your actions ... rules and regs are not that important ;)

Now with every man and his dog being experts in this field ... it just makes it that much worse. 

 

 

 

 

 

 

 

 

It is a big problem for us non DIY'ers because most of us average people don't know any rules or regulations, because we are not in that industry. We put our trust in the solar installer and electrician and we have no way of knowing if it is correct or not. Or if it follows regulations and/or standards. 

I have a COC from the electrician for the AC side of things. Is there something similar for the DC side of things?

 

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Another option to consider is "split trunking". This is rectangular trunking that is fitted with one (or more) internal dividers - so separating the AC wiring from other wiring (DC , LAN cabling etc.).

I have used the Efapel 10-Series trunking that I got at AC-DC. See https://www.efapel.com/en/products/cable-trunkings/10-series-distribution. This is a bit more expensive than regular trunking, but looks way more professional. You can buy a range of corner, t-piece and end-plates that make this very easy to work with.

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Thank you @isetech for your contribution, my coc was more or less done like that, it took the electrician more time to write up the coc than to do the actual inspection and walked off with his R1500, now i am having it re-done in the right way, HOPEFULLY, with me personally supervising what the electrician does.

Edited by Tariq
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18 hours ago, FixAMess said:

FYI - DC wiring is supposed to run in metal trunking, not plastic trunking.....

Check the stds as mentioned above.

To me, just an average Joe, this seems like a bad idea. Putting any type of electrical cabling in metal housing is asking for trouble. If the cable is "nicked" or perished, and it touches the metal, then there could be big problems. It is one massive conductor after all.

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1 hour ago, NigelL said:

Another option to consider is "split trunking". This is rectangular trunking that is fitted with one (or more) internal dividers - so separating the AC wiring from other wiring (DC , LAN cabling etc.).

I have used the Efapel 10-Series trunking that I got at AC-DC. See https://www.efapel.com/en/products/cable-trunkings/10-series-distribution. This is a bit more expensive than regular trunking, but looks way more professional. You can buy a range of corner, t-piece and end-plates that make this very easy to work with.

from what I understand, the DC wires should be in a metal trunking. that means you will definitely need to have two separate trunkings, no other options 🙂

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17 minutes ago, hoohloc said:

from what I understand, the DC wires should be in a metal trunking. that means you will definitely need to have two separate trunkings, no other options 🙂

I am not aware of any officially published standard that says this.  There was some discussion about routing solar cables in metal conduit when running over longer distances (e.g. between buildings etc.). The split trunking is widely used for routing AC and DC cables, in solar installations, in many countries.

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6 minutes ago, Speedster said:

Do you have any source to back this up?

I'm not an electrician, I have never claimed to understand nor know a lot about SANS rules. All the information that I have been exposed to, about this topic, I have read from this threat. If you have read the whole threat, you will see my comments, that I never knew that you are not supposed to mix AC and DC wires. So, to answer your question, NO! I do not have any source to back that up except the information from this threat and I trust people on this forum to be more knowledgeable than me and I do not think that they will mislead anyone, me included, on purpose. Maybe your question should be directed to @FixAMess , not me 

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12 hours ago, Vassen said:

The only thing I can find about it is related to 

1. Lightning protection section 5.4.6

2. Bonding section 5.4.5.2.3

3. Surge protection section 6.2.6

EDIT: Sorry I see you didn't say it requires metal.  You were responding with the only sections you think mention metal.  Kept my response below for posterity, because I frankly don't see any evidence of "DC requires metal pipes" story

Do you have an older version of the standards?  Your numbers are not the same as SANS 10142-1:2017 Edition 2

Secondly: What does a DC install have to do with lightning protection?

Bonding is about bonding your water pipes and gutters, what does that have to do with DC?

Same for surge protection, it has nothing to do with DC.

---

You should be looking at this section:

image.thumb.png.f19ce7447113912af050110bdb916d5d.png

Edited by Gnome
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3 hours ago, coachpotato said:

It is a big problem for us non DIY'ers because most of us average people don't know any rules or regulations, because we are not in that industry. We put our trust in the solar installer and electrician and we have no way of knowing if it is correct or not. Or if it follows regulations and/or standards. 

 

Let me just rant a bit here.  Because a lot of the guys who CAN issues CoCs shouldn't.  Or they issue it for things that are outside their wheel house.  My partner works in the building industry as a professional engineer for the HVAC and wet services side.  Granted electrical isn't the area she signs for, but the problem is wide.

As an engineer you design a system and the installer that issues the CoC should follow the instructions to the T.  Engineers are designers and installers are doers.  Whenever the installer deviates you are screwing a system that was built using very specialized calculations and was approved by the local municipality.  If it sounds elitist, it is only because you haven't been on the other side.  The software and calculations involved are super expensive and have years of study behind them (ie. thermodynamics for liquid based services).

The electrical industry is different here, there are not professional engineers that sign for electrical installs.  Probably because electrical is so old.  But this is, in my opinion, why every yahoo installs it their own way.  A solar install shouldn't be designed by an electrician.  The overall design should be done by a competent engineer.  If they copy that design for multiple install sites, fair enough.  But electricians are following guidelines, they lack a significant amount of theory you get when doing a degree.  The problem with electricians doing the design is, they don't know what they don't know.  They know the regs and nothing more.  So if a safety device should be there but it isn't mentioned in the current version of the regs, well it isn't even going to get considered.

3 hours ago, coachpotato said:

I have a COC from the electrician for the AC side of things. Is there something similar for the DC side of things?

CoC covers the entire installation of the house.  Unless the CoC was only issued for a part of the install. A CoC is about covering the electrical install of a home.  The same happens for a Geyser (also need a CoC there).

Edited by Gnome
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14 hours ago, Gnome said:

SANS 10142-1:2017 Edition 2: Wiring of premises isn't a suggestion book.  It lists the rules and requirements for a domestic install.  There are no "hey do what you want but we recommend".  Pretty much each section lays out a number of rules related to a specific topic.

They even go further to say you shouldn't put AC from one power source in the same conduit as another AC power source (ie. you can't run you inverter AC wire in the same conduit as your Eskom AC).

But the DC requirement is pretty obvious unless you don't know what you are doing.  Almost everything in SANS 10142-1:2017 is about safety.  And when you run AC and DC in the same conduit, if any cable were to get nicked and get in contact with the other, your entire DC installation is at mains voltage without any of the AC safety equipment.  Nicked cables are the most common cause of electrical faults and happen in most homes, so it is an obvious rule.

South African Bureau of standards.  These SANS document regulate every industry.  Plumbing, Electrical, Buildings, etc.  Just about anything that is legal to use in this country will either state which SANS codes they comply with in the manual or on the product itself.  You can't legally sell almost anything in SA without complying with one or more of the SANS standards.

Where does it say that?  I just logged into my access portal to make sure I have the latest edition and I can't find anything about that in the standard.

This is understandable, when you talk about conduits then Yes. This is common sense, you can not run AC and DC wires in the same conduit and shouldn't be running different wires from two or more different power source in the same conduit. Trunking is something else, you have lots of space in a trunking and I do not see why they will say you shouldn't mix AC and DC wires in trunking. If that is the case, that means the same will apply to cable trays where you have DC, AC and network cables sharing the same cable tray 

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6 minutes ago, hoohloc said:

This is understandable, when you talk about conduits then Yes. This is common sense, you can not run AC and DC wires in the same conduit and shouldn't be running different wires from two or more different power source in the same conduit. Trunking is something else, you have lots of space in a trunking and I do not see why they will say you shouldn't mix AC and DC wires in trunking. If that is the case, that means the same will apply to cable trays where you have DC, AC and network cables sharing the same cable tray 

For trunking I don't think there is a difference because the same risk exists.  But I could have sworn they run cables from both power and other systems (ie Air Conditioning systems logic cables) in a cable tray.  But I'll confirm.  I can't see anything explicitly in the regs other than, keep your AC electrical wire away from your non-AC electrical stuff.  I expect the answer is going to be no mixing in a cable tray or you need to put it in a conduit or something.  But TBD.

Edited by Gnome
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